A pre-mortem is intended to be a conversation among all project stakeholders before starting a project to discuss what is expected, what could go wrong, what timing looks like, etc.
We have a pre-mortem meeting to get an understanding of the business and the analysis before we start. What obstacles might we face? What is the timing? Do we understand the business model and its drivers? What don't we know? What could make this analysis go sideways?
It is hugely helpful to have some understanding of the business before we go into it. At Lucky8, we wasted a lot of time in some analyses b/c we didn't have the background understanding of the business model going into it. As much upfront understanding of how the company does business and accuracy of information as possible is important.